Naoto Kan: “Japan Was Invaded by an Invisible Enemy”

Kan was Japan’s prime minister from June 2010 until August 2011, when he resigned amidst criticism that he mishandled the government’s response to the earthquake, tsunami and nuclear disaster. Here he describes the key events during the crisis, including his controversial decision to visit TEPCO during the chaotic early days, and offers a warning about nuclear power: “The world shouldn’t race to rely on nuclear power. Let’s create societies that have renewable energy at their center.” This is the translated and edited transcript of an interview conducted on Nov. 28, 2011.

On the 11th of March, [2011] what were you doing and where?

I was at an Accounts Committee [meeting] for the House of Councillors of the National Assembly. There was a morning and afternoon session, and the earthquake occurred while I was asking questions at the afternoon session.

The chandelier on the top of the ceiling was swinging wildly. … It was right above the people in front of me, and I wondered if they would be all right. I kept looking up, watching the situation.

What was the shaking of the earthquake like?

The tremors were large. They rocked everything back and forth, and they continued for a very long time. I knew it was a big earthquake … to feel it in Tokyo, in the National Assembly.

From there how did you act?

When the shaking subsided somewhat, the head of the committee recognized this was a major earthquake. So he immediately adjourned the committee, and I returned from the National Assembly to the Prime Minister’s Office by car.

Then a tsunami came. How did you act, and how did you receive the information?

“Everyone agreed that we should vent. But no one could explain why it wasn’t happening. It was like a game of telephone with TEPCO headquarters in the middle.”

First, information on the earthquake started to come in, and we immediately set up the emergency disaster response headquarters.

Eventually, an hour or so after the earthquake, I received reports that tsunamis had hit. After that, the [Fukushima] nuclear power plant lost all power, and TEPCO [Tokyo Electric Power Company] officially notified me at 3:42 p.m. that we were facing an “Article 10″ situation.

At 4:45 p.m., I was notified that this time the emergency reactor core cooling device, cooling functionality, had been lost, in what is called an “Article 15″ situation. I received these reports one after the other.

That report came from whom? Directly from TEPCO or did it come from METI [Ministry of Economy, Trade and Industry]?

TEPCO is governed by specific rules of law and is required to report to the minister of METI. So I was informed directly by the minister of METI, or his staff.

… How did you find out about the tsunami? Did you see footage?

Later, a lot of very striking footage came out, but I don’t believe that at that point those kinds of tsunami images had been broadcast.

While listening to news reports, I set up the disaster response HQ and worked to gather information. During that time, information about the tsunami and the various stages of the nuclear plant accident were being communicated to me.

So you didn’t have much time to watch the news. You were handling all the information that was coming in?

When I was in the office I kept the television on, and at the same time I was listening to various reports.

How did you feel when you first heard about Fukushima’s situation?

I was told that all power had been lost, and my first thought was, “How could that have happened?” Fundamentally, even if power is lost there is emergency power, and if that is turned on then power is restored. I was wondering why that had been lost.

When power was lost, the cooling system stopped, creating what is legally called an Article 15 situation. When I heard that, I thought the accident had become extremely serious, what is called a severe accident, and I knew that if we left it, it would melt down.

The power source, or at least the cooling system, had to be restored by any means possible. When I got that news, I felt the situation was extremely serious. I thought it was a terrible situation.

After that, what orders were given from the prime minister’s office and how did the response unfold?

We immediately set up a response room at the prime minister’s office. After that, the minister of METI informed me about the procedure through which a nuclear emergency is declared, which we did.

An emergency response headquarters for the earthquake and tsunami had already been created, but in parallel with that, we also set up the nuclear disaster response headquarters.

These two headquarters were set up in parallel at the Crisis Management Center at the Prime Minister’s Office, and we continued to gather information.

For the nuclear accident in particular, I personally gathered relevant people together. I brought together TEPCO, NISA [Nuclear and Industrial Safety Agency], and NSC [Nuclear Safety Commission] representatives, the Minister of METI, and a number of aides and secretaries into a room in the Crisis Management Center, where we listened to incoming reports and made decisions on the issues that required some sort of decision.

What type of decisions did you talk about there, in detail? Did TEPCO ask you for things?

Yes that’s right. First of all, we conducted a certain number of legally required procedures and gatherings for meetings, explanations to nongovernmental parties and the like.

At the same time, TEPCO wanted EGCs [emergency generators], since power was out and the cooling system halted. If they had EGCs, if they could connect them, at least the emergency cooling system could be restored.

So they asked for cooperation in transporting the EGCs. Many places like TEPCO’s affiliates, Tohoku Electricity, the American military, etc., have a variety of EGCs. TEPCO took the lead in determining what kinds of EGCs there were, saying they wanted to take them to the plant as soon as possible.

If going by land they wanted police cooperation from the government, and wondered if they should perhaps use helicopters, something I wondered about myself. I had them consult the SDF [Self-Defense Forces] and American military on whether they could carry the EGCs by helicopter.

Unfortunately EGCs are very heavy and using helicopters was impossible, so they took the roads. I contacted various places, and the police said they would take the lead. … Sending them was the first, the most important task.

Even just with the earthquake and the tsunami it was bad enough, but on top of that the nuclear disaster. How did you feel?

Both were very serious. The disasters have things in common, but at the same time they were very different. First of all, the most important task relating to the tsunami and earthquake was saving lives. So for that, I instructed the SDF to mobilize as soon as possible.

That and of course the police and the fire departments mobilized from each local government. The focus was on saving lives.

On the other hand, with the nuclear accident, we were concerned about how serious the accident would become, whether or not we could halt it.

The nuclear accident began with the earthquake and tsunami and gradually spread so I could not turn my attention away. I had to stay focused on both so it was difficult to handle.

The Chief Cabinet Secretary [CCS] is the right-hand man in the prime minister’s office, and I had him keep an eye on the big picture, including the earthquake and tsunami. I, of course, focused on both, but took the lead for the nuclear accident, looking at all the live information and managing the crisis.

How difficult to have both.

It was difficult. Even just one disaster would have been difficult. … As you started to understand one, then the other you would understand less and less.

It must have been difficult to manage two or three crises from the prime minister’s office.

Indeed. The earthquake and tsunami themselves caused massive damage. Now we had a nuclear plant accident on top of that. And the situation kept changing, so in that sense it was really difficult.

In particular the earthquake and tsunami … first of all the saving of lives, meaning the people who could be saved had to be saved as soon as possible. During the Hanshin-Awaji [earthquake in 1995], the main destruction was from collapsed houses, so rescuing people from under houses was the main task.

But in this case the main problem wasn’t collapsed houses, it was people being swept away by the tsunami, so the rescue effort was different. During the Hanshin-Awaji quake, the SDF were delayed. The prefecture delayed a request for SDF troops. I remembered this, so first of all I told the defense minister to send as many troops to the scene as soon as possible. Ultimately more than 100,000 troops were assembled by the SDF, and they were dispatched from day one.

However for the nuclear accident, the nuclear plant had shut down when the earthquake hit, meaning the reactors’ control rods had been deployed, and nuclear fission had stopped. That’s what we heard.

But later, power was lost, and the reactor lost its cooling functions. Even if the nuclear reaction is stopped, I knew that the decay heat from the fuel would cause the temperature to rise and rise, and if left as is, water would evaporate and the fuel would melt down. This new situation unfolded as a result of the tsunami.

So in that sense, we had to simultaneously deal with two crises that had very different personalities. I and the chief cabinet secretary were overseeing the entire emergency response, but I directed the CCS to focus mainly on the earthquake and tsunami response. I, of course, oversaw that as well, but I dealt directly with the nuclear plants. … We both were involved of course … but I paid more attention to the situation at the nuclear power plant.

The EGCs did not connect. How did you feel? Were you watching it the whole time?

TEPCO requested for the ECGs to arrive if possible by the end of the day on the 11th, by the 12th, and if that happened they would be able to restore cooling functions. So we sent ECGs by road from a variety of locations, with the first one arriving at around midnight.

When the news came in that it had arrived, I thought of course that they would be connected and start operating. So for a moment, I was relieved. Then after that, after a while, I was told that we can’t connect them.

It’s an electrical company, so I wondered why they couldn’t connect it. In the end they hadn’t anticipated certain things, like the plugs being a different shape etc., and there were many reasons they couldn’t connect it.

Furthermore, we found out later that the salt water had even reached the distribution panels, so they would not have been able to connect it anyway. As a result, the few hours we spent somehow trying to send the EGCs had no effect.

Like I said beforehand, had they planned even just a little for situations like sending EGCs, of course they could have been able to adjust the plugs that did not fit. But they completely failed to anticipate this type of a situation, which led to what happened. It was very frustrating.

At that time, had TEPCO reported to the prime minister’s office about the possibility of a meltdown?

Ultimately the EGCs took a while to arrive, but even if the reactors weren’t getting power, they had emergency cooling systems that would run for a few hours. Each nuclear reactor has a different character, but they have an emergency cooling function.

So at the time, I received reports that the emergency cooling system for reactor 1 was still functioning somewhat and that as a result there was water still covering up to two-thirds of the fuel rods.

However, in reality that was only what TEPCO and NISA thought was happening at the time. We found out later that they were completely wrong.

In actuality, five hours or so after the tsunamis hit, the reactor was already in meltdown. By the time the EGCs arrived, the reactor was already in meltdown. Even TEPCO operators at the plant failed to grasp the actual situation.

While I received reports from TEPCO, NISA and NSC, I was also asking many experts directly for their opinion. So at a very early stage, I had heard from these experts that there was a high likelihood that the reactor was in meltdown.

But the official reports were coming from TEPCO and NISA. If you compare that with what we found out later, they did not accurately grasp the condition of the reactor. Or to go a step farther, they had a mistaken understanding. This was later made clear.

The information wasn’t communicated correctly.

It wasn’t communicated, and at the same time it wasn’t known. The difference from say Three Mile Island was that at Fukushima, the central control room was dark, and with no power, various readings of pressure, temperature and the like could not be properly taken.

So they thought that the water level was at such and such a height, but the water-level gauge itself was not working. The gauge showed a stable water level, so the workers thought the situation was all right. But the water-level gauge itself was malfunctioning.

In the data we’ve researched, there is talk that NISA had already reported the possibility of a core meltdown to the prime minister’s office at 10:45 at night.

About reactor 2 … the prime minister’s office was told that if such and such happened then such and such could be the result. But even though the person responsible, head of NISA was right in front of me, I was not told this at that point. …

For reactor 2, emergency cooling functions were temporarily restored, so the events played out differently than forecast, which meant that because reactor 2’s cooling system was operating for more than 24 hours, the forecast was not accurate.

On the other hand, it became clear later that reactor 1 had melted down from a very early stage.

[How did you feel about] the lack of information?

If we had understood how the situation was evolving, then at the very least we could take that into consideration in planning a response.

But not knowing how the situation was evolving, or that inaccurate information was coming in, … looking back on it, I wasn’t anxious. I was very worried about not being able to understand what was actually going on. I wanted to have a grasp of the situation. We could only guess.

NISA and NSC can’t really talk about suppositions. Government offices do not really make guesses, on the contrary. So I asked for second opinions from many experts. “What do you think?” There were a number of experts who said that a meltdown had started from a very early stage.

Keeping that in mind, you made the decisions. How did you decide to vent?

Recently many things are being understood from TEPCO’s reports and such, but the pressure in the reactor containment vessel started to rise. If left alone, then the containment vessel would rupture from the pressure. If a rupture occurs, then a mass of radiation will be immediately released into the atmosphere.

To prevent that from happening, venting had to be done, meaning the pressure inside had to be released and lowered. TEPCO and those at the plant proposed doing this. They thought venting should be done, but doing so would externally release a certain amount of radioactive material.

This required ordering an evacuation of people near the plant. This order is given through the nuclear disaster headquarters and I was the head, so it was something that had to be done under my responsibility.

I got a report from TEPCO that the pressure was going up, and they asked me, “what should we do?” Then the TEPCO representative, NISA member, and the head of NSC included, everyone agreed the venting had to happen, that we would do it. So I said, “I understand. Do it. Let’s do it.”

When I said, “Let’s do it. Please do it,” of course it should have been communicated, but actual venting didn’t proceed. Even though everyone had agreed by the night of the 11th that venting should happen, it took until the afternoon of the next day for venting to be done.

At the time I wondered why it could not be done and I asked many times. The TEPCO person in charge, who was in front of me, said “I don’t know the reason.” There were many guesses.

Looking at it recently, the technical problem was the biggest. To vent, there are two valves. Typically, they are valves that are opened electrically. But because there was no electricity, they could not be opened. So they tried to open the valves manually, but there was no manual for opening them manually. So they brought in a blueprint that detailed all the piping, and looking at that, they guessed how to open it and made preparations to do so. That took some hours. This has all come out in recent reports.

Either way, everyone agreed venting was necessary, but because of technical issues, it actually took place the afternoon of the next day.

There are reports that on the site they thought the pumping of seawater should take priority over the venting. Was there such a discussion within the prime minister’s office?

This is a very important issue. Everyone knows that ultimately water had to be pumped in. At that point, there were reports that there was water remaining in the reactor, that the water level was still plus something-hundred above the fuel rods. Then they temporarily did not know. Then after a while the fuel rods were up to two-thirds covered. In other words, the water level was decreasing but remained, and the cooling system was still somewhat operational.

This is what TEPCO and NISA were judging and reporting to be the case. And then they would say that the emergency cooling system was not working. The information itself was very confusing.

People have said that water should have been injected from early on, but at that point, TEPCO probably still thought that there was water. Additionally, in order to inject water into the reactor, the pressure inside the pressure vessel had to be somewhat low or water wouldn’t go in.

The pressure vessel was experiencing about 10 times the pressure of the containment vessel: 40 atmospheric pressure, 50 atmospheric pressure. It was high. So for first responders like the fire department, the pressure in the pressure vessel had to be lowered. Perhaps delays occurred because that could not be done.

Whether the reason was because of a judgment that water remained, or because the pressure in the pressure vessel was so high and water could not be pumped in … that is what the accident investigator is investigating right now, and it will become clear.

Based on uncertain data, you had to make important decisions. The pressure must have been great.

The prime minister has to make political decisions such as ordering the SDF to transport the EGCs, asking the cooperation from the police — that sort of thing.

But purely technical problems are not dealt with as political decisions. They involve assisting experts such as TEPCO based on what they say should be done. The most important action of course at the time was making sure that people living near the plant were not harmed, and that they were evacuated as quickly as possible.

I think the first evacuation was on the 11th, at around 9:00 at night. NISA said that there was still water in the reactors, but this was inaccurate. We could not deny the possibility that there was a meltdown occurring.

So the evacuation, this was my responsibility, or authority as the head of the nuclear disaster headquarters, so I ordered it.

The possibility of a meltdown was not made clear in the press conferences.

There are many expressions, but that was NISA’s opinion. What the chief cabinet secretary said in press conferences was based on NISA’s views of the situation.

NISA’s views were very vague. I was hearing from NISA and others, but those others were not at the plant. The information from the plant came from TEPCO to NISA, or from TEPCO itself. They strongly felt that the reactor cores had not gone as far as a meltdown.

Administrative organizations … how should I put this … choose their words carefully. As a result, a wrong view of the situation was given to the chief cabinet secretary by NISA, and he made announcements at press conferences based on that.

Why did you go to Fukushima, and what did you do?

I thought of going because in the debate at the prime minister’s office over venting — a debate that included members of TEPCO — it was unclear whether our opinion was being accurately communicated to Fukushima Daiichi. And it was unclear whether what was known at the plant was being accurately communicated to us.

Everyone agreed that we should vent. But no one could explain why it wasn’t happening. It was like a game of telephone with TEPCO headquarters in the middle.

At this rate, there would be no way to take action, so I thought I would go and listen to what the person in charge at the plant had to say. I thought that was important, and the next morning, early in the morning I went to the plant and met and talked with the Fukushima Daiichi plant manager Mr. [Masao] Yoshida.

I said, “Please vent,” and he said, “I get it,” and showed me his plan, and explained how they would be doing it. The driving force behind my visit to the plant on the morning of the 12th was because no one could tell me why the venting operation was being delayed. So I determined that it was necessary for me to talk to the person in charge at the plant.

What did you think when you first went to the site and saw the disastrous scene?

I went to a place called the ERB (Earthquake-Resistant Building). This was before the explosion, so externally you couldn’t see any changes to the reactors themselves.

Then later, from an aircraft I saw the tsunami and earthquake damage, which in and of itself was horrible. All of the recent footage of the nuclear plant was taken after the hydrogen explosion, but at 6 a.m. on the morning of the 12th it was not yet in that state.

Was there a difference in opinion between Mr. Yoshida and [TEPCO Vice President] Mr. [Sakae] Muto?

Mr. Muto said almost nothing. It was Mr. Yoshida who answered almost all of my questions. I wondered what was going on with Mr. Muto. Mr. Yoshida at least answered my questions to the point I felt “this person understands the situation.” I trusted him.

There are some people who say you didn’t have to go to Fukushima Daiichi, that they were as busy as it was.

There are many ways of looking at things. But in this case, if information had been communicated accurately to me, had decisions been made on a high level, and if appropriate advice had reached me, then I may not have needed to go directly.

But thinking back about the situation, had I stayed at the prime minister’s office and listened to NISA or unclear reports from TEPCO, I don’t think I would have been able to take the appropriate next steps.

In this kind of situation there is a person who gives the commands. In the case of an airplane it is the pilot, in the case of a nuclear power plant it is the plant manager.

There were nuanced differences in the decisions being made by TEPCO headquarters and the plant manager. I was able to communicate directly with Mr. Yoshida, and I believe that one of the main reasons I didn’t make incorrect decisions was because I had initially met with Mr. Yoshida.

When you got back, you held a meeting at the prime minister’s office. Was there any discussion of the possibility of a hydrogen explosion, or about how events would unfold from there?

I had actually asked the chairman of the NSC about the possibility of a hydrogen explosion on the 11th. The chairman told me “No, that is not possible. There is nitrogen inside of the containment vessel, so it’s not possible.” That was his explanation.

Later, a hydrogen explosion actually happened, but he said, “No, what I said was that there couldn’t be an explosion in the containment vessel,” that the explosion was outside of the containment vessel … so the wording changed.

At the time, I don’t believe that TEPCO, the NSC or NISA considered the possibility or danger of hydrogen escaping outside of the containment vessel. I was told in general terms that a hydrogen explosion was not likely to happen.

Then the explosions happened on the 12th and on the 14th. So the prior forecasts ended up being completely wrong.

Did you get frustrated with TEPCO, NISA and the NSC?

They couldn’t properly assess the situation, whether that was the reactor pressure, the water level, temperature… which I believe was caused because the system was not sufficiently prepared

Everyone tried their best after March 11th, but because there had been absolutely no advanced planning done prior to March 11th, in the end the forecasts proved wrong.

If you are unable to understand the cause of a problem it is impossible to solve it. So I strongly felt the crisis that first week.

How did you hear about the explosion on the 12th?

I was talking to the leader of the opposition party at the time, but I didn’t receive a report just then. The meeting concluded, I returned to my office, and it appeared that something had happened. An official report came from TEPCO via NISA about an hour later.

At the time, the type of explosion that had occurred was not properly communicated to the prime minister’s office, though later we found out that it was a hydrogen explosion. They probably did not know.

The footage on TV at the time –

The television in the office was kept on the entire time, but at first the footage was broadcast locally. It took a little more time to be broadcast in Tokyo. I think it was after about an hour.

There must have been reports from NISA and TEPCO all the time, but did you not understand them?

It was not explained to me that the reason for the explosion was that hydrogen leaking from the containment vessel had collected in the reactor building and exploded. The cause of the explosion was unknown. I was only told that “We do not know for sure, but there seems to have been some sort of explosion.”

Mr. Yoshida said in a recent interview that when reactor 1 exploded, he himself didn’t know what kind of explosion had happened. He was concerned that a lot of radiation would have been released had the explosion been nuclear, and that they would lose their lives.

When workers returned from the plant, it appeared that … the containment vessel itself had not exploded, only the reactor building had exploded. He talked about this in a recent interview.

Probably even at the plant, when the first explosion happened and there was a big bang, I doubt they initially knew what had caused the explosion.

There is talk that TEPCO hesitated on the pumping of seawater, had stopped it.

Fresh water was already being pumped in, and when fresh water ran out, there is only seawater left. So TEPCO and our office made it a priority to inject water. That was needed the most.

If fresh water ran out, then they would pump in seawater. Everyone agreed this was the natural thing to do.

There are reports that [Nuclear Safety Commission Chairman] Mr. [Haruki] Madarame hesitated because pumping in seawater could potentially cause re-criticality.

That is not accurate. That was not so. [TEPCO Executive Vice President and Chief Nuclear Officer] Mr. [Ichiro] Takekuro told us that a little time was needed to switch from fresh water to seawater. That’s when I asked some of those gathered if re-criticality could occur, and Mr. Madarame said something like, “I can’t say the possibility is zero.”

So I said that if there was some extra time available before switching to seawater, then we should consider mixing in boric acid as well.

Neither I nor Mr. Madarame tried to stop the pumping of seawater. But the confusion that followed, Mr. Takekuro said it would take about an hour and a half, but in actuality seawater had started to be pumped in at an early stage.

If you read the later reports, there was talk of re-criticality, and injecting seawater, but the talks had not gone that far, meaning it took the form of Mr. Takekuro stopping it.

According to initial reports, Mr. Yoshida said, “I understand,” and stopped pumping before starting again later. But in reality Mr. Yoshida made a decision not to stop pumping. That is, in later reports, that he did not stop it.

If there is a danger, the head of plant has the authority to act. Those at the plant understood the situation better, and earlier on had been able to switch to seawater. After that they continued without stopping at all.

Intentions were not being properly communicated through intermediaries.

There was talk by TEPCO about a withdrawal the evening of the 14th, morning of the 15th. What was your reaction to this extraordinary request?

I was in the drawing room next to the office, taking a nap. Then at about 3:00 in the morning, my secretary came and told me that Minister of METI, [Banri] Kaieda, wanted to consult with me. So I went out to the office. The members had gathered nearby, so I listened to them there.

They said: “TEPCO says they cannot control it anymore, so they want to withdraw. What should we do?” So I asked everyone’s opinion.

I thought withdrawal was out of the question. If they withdrew, six reactors and seven fuel pools would be abandoned. Everything would melt down. Radiation 10 times worse than Chernobyl would be scattered.

They said that TEPCO President Masataka Shimizu had mentioned it. I asked them to call Mr. Shimizu, and I directly met and talked with him. Mr. Shimizu would not say clearly that they wanted to withdraw, or that they wouldn’t withdraw.

I thought that it would be dangerous to leave things like this, so I said to him, “Let’s create a government and TEPCO response headquarters” and he said, “I understand.” So I became the head of the integrated response headquarters, and the minister of METI and the president of TEPCO became the deputy heads, and [Goshi] Hosono, an aide, became the associate deputy head. Where we would place this became very important.

If it was placed in the prime minister’s office, then like usual we would be hearing reports from those who came from TEPCO, and like a game of telephone, communication would not be good. So we decided to create it at TEPCO’s head office. Then I went to TEPCO headquarters to have our first meeting.

That was about 5 a.m. on the 15th. Once at TEPCO headquarters, their office was connected to the Fukushima site 24 hours by videoconference, allowing everyone there to share information. About 200 TEPCO employees gathered there.

I said, “This is a very tough situation. But you cannot abandon the plant. The fate of Japan hangs in the balance. All those over 60 should be prepared to lead the way in a dangerous place.” I said this very strongly.

After that, TEPCO did not talk about withdrawal again.

When you were in a car headed towards TEPCO, what were you thinking?

We started to think about how far the accident would spread. I asked people to do a simulation of what could happen. The worst-case scenario was an evacuation of 120 to 190 miles around the plant. If that happened, Tokyo would grind to a halt. Japan would grind to a halt.

I felt that sense of crisis for the first few days, and it was during that time that there was talk about a withdrawal. I felt very strongly that withdrawal could not happen, and with those strong feelings I got in to the car.

Those strong feelings had quite an impact on the situation.

From the perspective of worker safety, had this been just a conventional fire, you have the choice to retreat and wait until the fire burns out rather than staying and putting it out

But with a nuclear accident, you can’t just watch until it burns out. It will not burn out. After that the situation gets worse. So to me that option was not possible.

Otherwise, we’re handing Japan to an invisible enemy. This would affect not just Japan — but the whole world.

As a country we had a responsibility to the world. It wasn’t acceptable. I felt a very urgent sense of crisis.

The morning of the 15th, while you were still at TEPCO, there was another explosion. How did it feel, seeing that?

As I said before, on the morning of the 15th at around 5 a.m., I went to visit TEPCO headquarters. There were about 200 employees gathered there, and there were video links to other locations. I believe that Mr. Yoshida was listening to me as well. After I spoke, I moved to a small room nearby to have further talks with TEPCO executives. That’s when the explosion happened.

I wasn’t talking to Mr. Yoshida at the time. I was in the room next to the main room, where we were deciding who to place in the integrated emergency response headquarters.

At that time as well, the type of the explosion was not immediately determined. I think even now they say that it was not a hydrogen explosion. I think the suppression chamber for some reason was destroyed.

I’m not sure if this was a problem with the Mark 1 reactor that had previously been pointed out to the manufacturer, I don’t know for sure if it is the same problem, but the explosion was a little different from other hydrogen explosions.

On the same day, the U.S. ordered its citizens within 50 miles of the plant to evacuate. Did the U.S. contact you about this before or after?

The Americans established a 50-mile evacuation zone at an early stage, and they told us that that they had given this order to their citizens. I think it was earlier than the 15th.

Did America think the matter was more serious than Japan did?

My feeling is yes. America and other countries did even more so that Japan. For example, some countries closed their Tokyo embassies and moved to Osaka.

America said that families should move 50 miles away from the plant, but the embassy officials stayed in Tokyo and stood firm.

Were you hesitant about the U.S. and other countries becoming involved in Japan’s crisis?

I talked to President Obama on the first day, and later to Ambassador [John] Roos. At the time, apparently America was concerned that Japan was hiding information or holding it back.

But as I said before, our grasp of the situation itself was not accurate, so from America’s point of view, they thought perhaps we knew about a meltdown but we were not saying it.

But NISA didn’t actually think that the fuel was melting down, and when we reported this, the Americans were not in agreement. That’s where some mistrust occurred.

That problem was eliminated on the 15th when we set up the integrated response headquarters at TEPCO. We called in an American expert, had him sit in, and shared all the information. That’s when those problems were mostly eliminated. I don’t believe we ever had an American expert at the prime minister’s office.

How did you decide on the SDF helicopter’s operation?

There are reactors 1, 2, 3 and 4, but reactor 4 was undergoing a routine inspection and had no fuel in its reactor. It was empty. Reactors 1, 2, 3 had been affected by explosions or had leaked radiation. Reactor 4 was empty, so it posed no danger at all.

Yet in reality it contained fuel that was not completely spent. The fuel was still in use. They had transferred it to the pool during the routine inspection. If the water in the pool is drained — since the cooling system is stopped — if the water in the pool evaporates the fuel rods inside would melt down.

There is no lid on the pressure or the containment vessel. If hydrogen from adjacent reactors caused a hydrogen explosion, because there is nothing on top, radiation would be directly dispersed into the atmosphere. So whether or not there was water in reactor 4 became a very big problem. That is what America was most worried about at the time: Isn’t the pool empty? Water has to be put in by any means.

When an SDF helicopter flew by taking video, they caught a glimpse of the water surface and water seemed to be inside. We found out later that some water remained, but either way putting water into the reactor 4 spent fuel pool became extremely important.

On the 16th, we asked the SDF to try and dump water in from above. At the time, the radiation level above the plant was very high. A scout helicopter went ahead and indicated that it was too high, so they couldn’t do it on the 16th.

But the next day, the defense minister called and said, “Please do what you can.” And they said, “Our job is to protect the lives of the people, so if we’re given the order, we will go.” So the SDF flew a helicopter that they had lined with types of metal sheets and dumped water on the reactor.

The SDF operation encouraged others, and the police, fire departments and many others started to say that this problem was not just TEPCO’s accident, it was Japan’s. Everyone started to feel strongly that this was about whether Japan would survive, that the country was suffering.

From then on the atmosphere changed, with all those involved desperately doing what they could, even if it was somewhat dangerous. On the 15th, the integrated response headquarters was set up. On the 16th, the helicopters flew, and from the 17th, water was dropped from the air. Then from the 18th, the fire department and police used a device called a “giraffe” to pump water in. The turning point for all of this was the SDF’s water drop.

The SDF’s operation on TV did not look like it had much effect, but you’re saying that in a different sense it had an effect?

That’s exactly right. Due to high levels of radiation, the water had to be dropped from a high altitude so perhaps not a lot of water went in. But the operation became a turning point and the atmosphere thereafter became “We’ve got to do this.”

I also asked Tokyo Gov. [Shintaro] Ishihara to send the Tokyo Fire Department, because they had the largest capacity. Firefighters from Kawasaki and Osaka came as well, and the Metropolitan Police Department brought in water-cannon trucks.

We assembled water-spraying vehicles — we called them many things like giraffe and elephant — from around the world, allowing us to pump water directly into the reactors.

So in that sense, the SDF flying on the 16th and dropping water from the 17th was a turnaround. Until then, we had been pushed and pushed by an invisible enemy. But on the 15th, we created the integrated response headquarters, and from the 16th we started to supply water. Finally, the system was in place. The turnaround began.

From there would you say everything was under control? Or was that much later?

No, the situation wasn’t brought under control until much later. At this point, we had finally started to supply water to the reactors. The next big problem that occurred was that the more water we put in, the more it overflowed, and it overflowed into the sea.

At that stage the situation wasn’t yet under control, but we had been pushed up against the wall and we were finally able to stand our ground.

It was around July 9, when I thought that we’d finally managed to take control of the situation. Stage one [of the TEPCO recovery roadmap] had almost been achieved as planned. I remember feeling at that time that we had finally been able to achieve some control.

Looking back now, what information do you wish you had? What did you wish had happened?

Most of that would be before March 11. None of the forecasts functioned as they should have. After March 11, the problem was that we didn’t know the actual situation. Not having that knowledge was a problem. So of course it would have been better had we understood what was going on. But because of the lack of preparation prior to March 11, for example not knowing reactor 1’s water level, or that the water-level gauge and the actual water level were different, we did not have that information because a total loss of power had not been anticipated.

Given the unanticipated total loss of power, the fact that the disaster stopped there was because the first responders tried so hard. In the end, that it did not spread any further was God’s will. That’s what it was. That first week we walked a razor thin line.

What was your worst moment?

It had to be the explosions at reactors 1, 3, and 2, and the fear that the fuel rods in the reactor 4 pool might melt down, or that the reactor 4 spent fuel pool might crumble due to an aftershock, in which case there would be nothing we could do, although I had immediately ordered reinforcement. The spent fuel in the pools of reactors 1, 2, 3 and 4 might melt down, and if that happened, particularly in the case of reactor 4, a large amount of radiation would be released.

Those were the sorts of things that scared me most, for if they happened, there was the danger that areas within 200, 300 km would become uninhabitable, and I felt a shiver down my spine.

Who do you think is responsible for this crisis?

I think the biggest responsibility lies with the generations of government who promoted nuclear power, the governments who, on the one hand promoted it, while neglecting the proper safety measures. The generations of government I think have the biggest responsibility.

The inability to prevent the disaster was I believe the government’s fault. In that sense it was a man-made disaster. In addition, although TEPCO as a business should best understand nuclear power safety, they didn’t think it necessary to think of total power loss.

Originally the plant location was a hill 35 meters above sea level, but they bulldozed it down to 10 meters and built a nuclear power plant there. In spite of the fact that tsunamis had hit the area many times, they chose this location. I think in those areas, TEPCO’s responsibility, along with the government’s, is great.

On the 12th, the evacuations started, and then the evacuation zone was expanded. NISA said it gave the prime minister’s office the SPEEDI [System for Prediction of Environmental Emergency Dose Information] data. Why was it not used?

The prime minister’s office is a building. There are NISA members there, and some times NSC members too. So SPEEDI results may have been communicated to the NISA contact at the prime minister’s office, but no one from NISA said to me or to the chief cabinet secretary: “These are the SPEEDI results that should be taken into consideration when planning the evacuations. ” I was given no such explanation.

Because the data wasn’t communicated, I had no idea at the time that they had made such forecasts.

In May 2011, you announced a new energy policy, and cold shutdown was achieved. Are you concerned things will go back to the way they were even after the announcements of the new plans?

I do not think the situation will return to how it was. First, the administration of nuclear power will change. This means that the current form of NISA will be abolished, and the nuclear safety ministry will be separated from METI and placed in the environment ministry.

This was decided in my cabinet, and policy is moving in that direction, with current [Environmental] Minister [Goshi] Hosono taking the lead. This change will take effect in April 2012. So in that sense the administration of nuclear safety will clearly be changed.

As for energy in general, until now the plan was to generate 53 percent of electricity by nuclear power by the year 2030. But we are now back to square one. A new energy policy will be considered, but at the very least, renewable energy will make up 20 percent of the total by 2020, which is what I suggested when I was prime minister.

Over the long term, we need to create a distribution system of energy that does not rely on nuclear power. This means energy conservation and the expansion and strengthening of renewable energy, which means less reliance on nuclear power and fossil fuels. These are the broad brushstrokes of where the new energy policy is headed.

When I left office, I made the passage of three bills a condition. One of them was the policy for the promotion of renewable energy, and by next July the details will be decided, so that’s how I think natural energy will greatly advance.

What you said about your worst estimation, the estimation of [having to evacuate] 200, 300 km, including Tokyo, it must have been a scary forecast. What instructions did you give, and how did you calculate, and what were the results?

I asked many associates to make forecasts, and one such forecast was a worst-case scenario. But that scenario was just something that was possible, it didn’t mean that it seemed likely to happen. I always kept that scenario in mind and did everything I could to keep it from becoming reality.

It was a blessing that the situation never got that bad.

[Your aide] Mr. [Manabu] Terada remembers going to you and telling you to turn on the television when reactor 1 exploded.

Wasn’t that reactor 3? I was talking to Mr. [Natsuo] Yamaguchi, leader of the New Komeito Party, when that news came in, and then I turned on the television in the prime minister’s office and saw it.

When it was reactor 1, there were a lot more people, so I do not recall seeing it there, I think I was in a room without a television, so I don’t think that was so.

… What did this crisis mean to you?

This is something that someone else has said. A man named Yu Sato said that in Japan, before the war it was natural to die for your country, and in reality, many people died for their country in the war.

After the Second World War, people in Japan no longer died for their country, and even that expression was no longer used.

With this nuclear accident, even if your life was in danger, if it was to resolve the accident, you had to do your best. It was the first time since the war that the government had made this decision. He analyzed it that way.

Having it put that way, I felt that way too. In general, telling people to escape quickly out of harm’s way is a politician’s or a prime minister’s responsibility.

But in this case, Japan was invaded by an invisible enemy, and when it was threatened with being shut down, escape was not an option. Fighting was the only way.

Fortunately at this point no one has died directly due to radiation exposure. But even if there were such risks, the government said, “Do your best. Do your best to resolve this nuclear accident.” I think fate placed me there as the prime minister.

For me it was a very difficult decision. But I thought it had to be done, and I did it.

What do you want to say to the people of the world about this?

The trend in the world right now is — not just in developed countries, but in developing countries including China and India — there is a movement to build more and more nuclear plants.

In Japan, the direct cause of this accident was an earthquake and tsunami. But the loss of power source can happen without an earthquake or tsunami.

For example, if there had been a nuclear plant in Libya and if Qaddafi had holed up in a nuclear reactor at the end and said, “If you attack, I will cut all power sources in the reactor and make it meltdown and destroy it,” what would have happened?

When the world has 1,000, 2,000, 3,000 nuclear plants, can we call that a safe world? I think we need to properly have this debate.

Next year I have been invited to Lagos, so by then I plan to consolidate my thoughts, but I feel that Japan and the world can supply sufficient energy without relying on nuclear power or fossil fuels. This type of society should be created, and I want Japan to be a model country for that kind of society. That is what I think.

The world shouldn’t race to rely on nuclear power. Let’s create societies that have renewable energy at their center. That’s the direction I want us to head in. That is my message to the people of the world.

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